Semiclosed cycle gas turbine plant



Sept. 8, 1953 v G. BOLSEZIAN 2,651,174

SEMICLOSED CYCLE GAS TURBINE PLANT Filed Oct. 28; 1948 6 GEORGES 5014.: LIAN INV NTORI Patented Sept. 8, 1953 UNITED STATES. PATENT-OFFICE Georges Bolsezian; Paris, France Application October 28, 1948, Serial No. 56,973 In France November 3, 1947 This invention relates to a semi-closed cycle gas turbine plant wherein the fluid of the closed part of the cycle is heated by the radiant heat of the combustion gas, and has for its object to have in the closed part of the cycle a clean fluid which cannot foul the compressors and the heat exchangers.

' According to the invention there are formed in the heater two parallel layers of fluid the first of which is formed by combustion gas and the second of which is formed by a clean fluid, said layers remaining in direct mutual contact, with the formation of a mixed zone only at their contact boundary, the second, clean layer being heated by the radiant heat of the first layer,

through radiant heat absorbing elements placed in the second layer, and at least the greatest part of the unmixed fluid of the second layer being separated again, after heating, to pass into the closed part of the cycle.

Other objects of the invention will appear in the following specification and the accompanying drawing, which represents by 'way of example two embodiments of the invention and detail modifications thereof.

Fig. 1 represents schematically a first embodiment of the plant according to the invention.

Fig. 2 represents a cross section of the heating surfaces of the plants of Figs. 1 and 3 taken on the line 2-2 of Fig. 1.

Fig. 2a represents a cross section similar to Fig. 2 showing a modified arrangement of the heating surfaces.

Fig. 3 represents schematically a second embodiment of the plant according to the invention.

The embodiment shown on Fig. 1 is a semiclosed cycle gas turbine plant in which an atmospheric air charging compressor l, a cycle compressor 2, a cycle turbine 3, an extraction turbine 4 and a receiver of useful work 5, for example a generator, are mounted on a common shaft. The exhaust, which in this embodiment is pure air and which leaves the closed cycle turbine 3 with a pressure higher'than' the atmospheric pressure, passes through the conduit 6, through a heat recuperator 1 and a cycle cooler 7 Claims. (01. 60-39.18)

lla.

fluid of the cycle turbine 3. It passes then through a conduit l0 and is divided into two parts. The first part of the compressed fluid enters the combustion chamber l l where it causes the combustion of the fuel and the resulting combustion gas is discharged through the outlet I I0 of the combustion chamber l I into the intake of the radiation heater Ila formed by a single conduit, in which said combustion gas forms a first, central layer of hot gas. The second part of the compressed fluid is led through a passage l lb surrounding the combustion chamber I I and emerges into the intake of the radiation heater Ila in which it forms a second layer, around said first layer. The outlet of the passage I lb has a common wall with the outlet llc of the combustion chamber II, so that the combustion chamber l I and the passage I lb form two parallel fluid inlet conduits at the intake of the heater Said first and second layers are parallel to one another and in direct contact with each other, and they mix partially only at the zone of their contact boundary. Said second layer is heated by radiant heat transmission, by ele ments l2 placed in the heater Ila, behind the passage llb. These elements l2 absorb the radiant heat of the combustion gases of said first layer and transmit it to the compressed air forming said second layer in which they are placed, so that it impinges them on their two faces. Figs. 2 and 2a show cross sections of two embodiments of the heat exchanger formed by the elements l2. The inlet of the combustion chamber II is so dimensioned that the quantity of fluid entering the combustion chamber II and consequently the quantity of combustion gas forming said first layer is less than the delivery of the charging compressor I. The surplus of the delivery of the compressor I over the quantity of compressed air passing through the combustion chamber ll passes through the pas- 8, and is again compressed to the working presat the same pressure with the exhaust fluid of the closed cycle. The fluid compressed by the compressor 2 passes first through the heatresouperator 1, where it is heated by the exhaust sage I It surrounding the combustion chamber, together with the fluid of the closed cycle, to form said second layer in the heater Ila.

An outlet conduit means l3 mounted at the exit of the heater Ila removes from the cycle a quantity of fluid which is led through a conduit l6 and actuates one or more extraction turbines 4. The remaining fluid leaves the heater I la through other outlet conduit means I5 and actuates one or more closed cycle turbines 3. The intake opening of the outlet conduit means l3 faces the outlet llc of the combustion chamber .II and is so dimensioned'with respect to the cross section of said outlet llc, taking into account the contraction of said first layer of combustion gas through heat transmission to said second layer, that the outlet conduit means l3 collects the whole of said first layer of combustion gas and at least the whole of said mixed zone at the contact boundary between the two layers, while the unmixed fluid of said second layer, which in this embodiment is pure air, remains out'of the'outlet conduit means 13 and passes through the other outlet conduit means 15 into the closed part of the cycle. The size. of the intake opening of the outlet conduit means i 3 is also such that the quantityof fluid removed: from the cycle through said outlet conduit means [3 is substantially equal to the quantity of fluid delivered by the charging compressorii and-in.-

troduced into the cycle.

Eventually, a part of the pure air heated by the elements l2 absorbing the radiant=heat of the combustion gases may be heated further by conducting surfaces M mountedin series-with theelementsl2 and traversed by the combustion gases.

Accordingwto another embodiment represented in:Fig.:3,1inrwhi0h-the sameelements are designated-by=thesame reference numerals as in Fig. 1,? the :fiuid removed frommh'ecycle passes also through-a abranch conduit l'l" and thus actuates the-extraction -turbinel aswell as a separate extraction-turbine Iii-coupled witha preliminary atmospheric:air charging compressor 59 which feeds the ch'arging compressor I mounted on the same shaft'as the-cycle compressor 2. The group I; 2;:3;:4, 5 rotates-:at constant speed, and the group l 8; I 9 at variablespeedi Figs: 2 and 2a represent-cross sections of the elements-J2 which=absorb the-radiant heat of around-thecombustion -gases andthey are im- 4 pinged on -theirtwo faces b'ythe compressed air.

I claim;-

1. Ina semiPclosed cycle gas turbine plant having at leastacycle compressor, a radiation heater, at leasta =cycle turbine; a heat recuperator and a cycle cooler, through which a fluid circulates ina closed cycle in th'e order cited, and which has a combustion chamberwith an outlet discharging combustion gas into said heater, at least an atmospheric compressor for charging the cycle-and at least-an extraction turbine for extracting iiuid from :the cycle, the improvement in its :fluidheatingandrfluid distributing means which includes two parallel-fluid inlet conduits at the intake of saidradiation heater, the first of said'inlet conduits zbeing formed'b'y said combustionchamber into which? one :part of the fluid is introduced to burn thefuel and from which the combustion-:gas isriischarged into said heater to form thereima :firstlayerof hot fluid, the second of said-:inlet conduits discharging fluiddirectly into saidheatento' form: therein a second layer of fluid: which. ;is1-:paralle1 to: said first layer and which'remainswin: direct contact with said first layer-, the fiuids-otsaid two layers being partially mixed only. at the zone of. theircontact boundary, radiant heat absorbingelements placedin said heater behind saidsecond. inlet conduit; substan-. tially in saidsecondlayer andiparallel to its flow, said elements beingarrangedsto absorb the radiant-heat-oLsaid. first-layer and-to heat the fluid of-.said .zSbGOIld slayer ion: their. .two; faces through heattransmitting contact... therewith, conduit.

means at the exit of said heater after said radiant heat absorbing elements, said conduit means having an intake opening facing said outlet of the combustion chamber and so dimensioned with respect to the cross section of said outlet of the combustion chamber that at least the greatest part of the unmixed fluid of said second layer remains out of said conduit. means, and other conduit means atithe exit of said heaterfor passing the unmixed fluid of said second layer into the cycle turbine.

2. A semi-closed cycle gas turbine plant having at-"leastraizcyclemompressor, a radiation heater, a cycle turbine, a heat recuperator and a cycle cooler, through which a fluid circulates in a closed cycle in-theorder cited, and which has a combustionichamber with an outlet discharging combustion gas into said heater, an atmospheric air charging'compressor delivering fluid to the cycle compressor and an extraction turbine for extracting 1 fluid from :the cycle, two parallel-inlet conduits at :the intake oft said radiation heater and anothersconduitbetween the cycle compressor: and the. radiation heater, saidlast mentionedcom duit dischargingscoxrrpressedfluid into 'said two inlet conduitsythe firslrofsaid inlet. conduits;- being: formed by said combustion chamber in .whichriuel is burned -and from .whichzthe;combustion:gas flow isdischarged intosaid .heater-,;andxthe. :sec:v ond of said .inlet:conduits...-being formed by;.a con-e. duit located around said combustion-chamber and :1 through; which the f uid:to ibe-heated .flows into said heater; the soutlet .ofrsaid. second inlet :conr; duit' having a ;.common;:wall.;with= said outlet of. ,1

the combustionphamber; theflow offcombustiony:

gas and -the;fi0lw -of; fiuid ito'..be-.heated forming; in said heater .two:parallel-.-:layers,of fluidwhich; remain in direct contactwitheach-other .and are partially mixed only ati the zone of their contact.- boundary, radiant heatabsorbing elements placed '2 in said heater behind-said second inlet conduit, substantially 'in;-.said1-secondlayer and parallel; to its flow, said elementsibein '1arrangedto absorb:-. the radiant heat: of; the-combustiongas of said A. first layer and being in heat-exchangerelation: on their two .faces ;.W-ith. ithe fluidz-ofsaid second layer, outletconduit means-at the exit or. said heater, after "said-:radiant .heat absorbing elements, said outlet; conduit means. being:in com munication with said extraction turbineand having an. intake I opening; in said heater, said intake opening facing l said: outlet of thecombustionw chamber and being so dimensioned"with-respect to the cross section of saidoutletoi the combustion chamber.- as -to-collect-.at least the totality'of. the combustion gas,.-.and..-anotheroutlet conduit means at the. exit-of said heaterato pass the fluid. remaining out of said .firstoutlet conduit means intothe cycle turbine..-

3. Asemi-closedcycle gas turbine plant having at least a cycle compressor, a radiation heater, a cycle turbine, a-heat recuperator and a cycle cooler, throughwhich afluidcirculates in a closed cycle in the. ordercited; and which has a combustion chamber withancutlet discharging com-. bustion gas into." said heater, an. atmospheric. air compressor for. charging the cycle andan extraction turbine .for. extracting fluid... from. the cycle,- said radiationheater. being formed by a, single conduit,.two parallel. inlet conduits at. the intake.-v of saidsingleconduit, the first .of said'inlet con-. duits being formedby saidcombustion chamber;- and the-secondofsaid-inlet conduits forming. theinlet passage bit-the. fluidito -bei heatedqincsaidc. single conduit, another conduit. leading fromthe...

outlet of said cycle compressor to said first and second inlet conduits and feeding said inlet conduits, the combustion gas discharged from said combustion chamber into said single conduit forming therein a first layer of fluid, and the fluid to be heated discharged through said second inlet conduit into said single conduit forming therein a second layer parallel to said first layer and in direct contact therewith, the fluids of said two layers being partially mixed only at the zone of their contact boundary, radiant heat absorbing elements in said single conduit, said elements being placed behind said second inlet conduit, substantially in said second layer and parallel to its flow, said elements being arranged to absorb the radiant heat of the combustion gas of said first layer and to heat the fluid of said second layer on their two faces through heat transmitting contact therewith, two outlet conduit means at the exit of said single conduit, the first of said outlet conduit means facing said outlet of the combustion chamber and being in communication with said extraction turbine, and the second of said outlet conduit means being in communication with said cycle turbine, said first outlet conduit means being arranged to divide again said two layers in two separate flows, the first of said flows comprising at least the whole of the combustion gas and passing in said first outlet conduit means, and the second of said flows comprising at least the greatest part of the unmixed fluid of said second layer and passing in said second outlet conduit means.

4. A semi-closed cycle gas turbine plant having at least a cycle compressor, a radiation heater, a cycle turbine, a heat recuperator and a cycle cooler, through which a fluid circulates in a closed cycle in the order cited, and which has a combustion chamber with an outlet discharging combustion gas into said heater, an atmospheric air compressor for charging the cycle and an extraction turbine for extracting from the cycle a quantity of fluid substantially equal to the delivery of said air charging compressor, two parallel inlet conduits at the intake of said radiation heater which discharge two parallel flows of fluid into said heater, the first of said inlet conduits being formed by said combustion chamber and having an inlet so dimensioned that a quantity of fluid less than the delivery of said air charging compressor is introduced into said combustion chamber to burn the fuel and from which the resulting combustion gas is discharged into said heater to form therein a first layer of hot fluid, the second of said inlet conduits leading fluid directly into said heater to form therein a second layer of fluid which remains in direct contact with said first layer, the fluids of said two layers being mixed partially only at the zone of their contact boundary, radiant heat absorbing elements placed in said heater behind said second inlet conduit, substantially in said second layer and parallel to its flow, said elements being arranged to absorb the radiant heat of said first layer and to heat the fluid of said second layer on their two faces through heat transmitting contact therewith, conduit means at the outlet of said heater after said radiant heat absorbing elements, said conduit means having an intake opening facing said outlet of the combustion chamber and so dimensioned with respect to the cross section of said outlet of the combustion chamber as to separate from said two layers a quantity of fluid substantially equal to the delivery of said air charging compressor and comprising the whole of the combustion gas and a fraction of fluid of said second layer heated through heat transmission, to pass them into said extraction turbine, and other conduit means at the outlet of said heater for passing the remaining unmixed fluid of said second layer into the cycle turbine.

5. A semi-closed cycle gas turbine plant as claimed in claim 1, in which a conduction heat exchanger for heating the fluid is placed in series with said radiation heater.

6. A semi-closed cycle gas turbine plant as claimed in claim 2, in which said radiant heat absorbing elements form a star shaped body in said heater.

7. A semi-closed cycle gas turbine plant as claimed in claim 1, having its atmospheric air charging compressor divided in two separate air charging compressors and having its extraction turbine divided in two separate extraction turbines, the first of said two air charging compressors forming a mechanically independent group with one of said extraction turbines and being driven by it, and the second of said two air charging compressors being mechanically connected with said cycle compressor on the same shaft, driven together with said cycle compressor and disposed in series with the first of said two air charging compressors.

GEORGES BOLSEZIAN.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,298,663 Traupel Oct. 13, 1942 2,341,490 Traupel Feb. 8, 1944 2,454,358 Traupel Nov. 23, 1948 FOREIGN PATENTS Number Country Date 212,104 Switzerland Feb. 3, 1941 212,269 Switzerland Feb. 17, 1941 228,271 Switzerland Nov. 1, 1943 844,442 France -2 Apr. 24, 1939 

